What is the meaning of Pause Frames and does it affect the interface traffic ?
The NE40E interfaces received a pause frames from its peer asking to reduce the transmitting traffic in order to not cause a frame discard , after the NE40E interface did not detect a pause frame coming from its peer , the alarm is cleared and the traffic sent normally to the peer.
Please refer to attached report.
By analyzing the DIAG file on the customer X NE40E router version , I have found below two alarms :
Apr 7 2011 00:59:27 ZBL_2.H IFNET/1/PAUSERISING:Slot=8;OID 18.104.22.168.4.1.2011.5.25.41.4.10 The PAUSE FRAME receiving rate is rising. (hwIfMonitorIndex=536871169, hwIfMonitorPauseFrameStatistics=0 76, hwIfMonitorPauseFrameThreshold=500, hwIfMonitorPauseFrameInterval=10)
Apr 7 2011 02:23:07 ZBL_2.H IFNET/3/PAUSERESUME:Slot=8;OID 22.214.171.124.4.1.2011.5.25.41.4.11 The PAUSE FRAME receiving rate resume. (hwIfMonitorIndex=536871169, hwIfMonitorPauseFrameStatistics=0 0, hwIfMonitorPauseFrameThreshold=500, hwIfMonitorPauseFrameInterval=10)
The first alarm " PAUSERISING " means that the NE40E interface received a pause frames from its peer asking to reduce the traffic sent from the interface so the peer can handle the old frames without discarding any incoming frame based of the flow control standard rule on IEEE802.3x .
By default , once the interface received a pause frame , it waits for a defined interval of between two consecutively pause frames and detect if another pause frame is received. So each interval the interface has to receive a frame but if the received frames are more than two frames in an interval the alarm will appear on .
The alarm reason is that the interface has received around 76 pause frames which exceeds the defined intervals.
If the received pause frames exceed than 500 frames the peer will discard some received traffic received frames .
If the consecutive time interval passed without receiving any pause frame the alarm will be cleared and the informational notification " PAUSERESUME " will be show up .